Compress JXL images.
Smaller JXL files made locally — nothing ever uploaded.
Drop JXL files here
or browse your files
Paste with ⌘V · or drop files anywhere on the page
Files never leave your device. Everything runs in your browser, nothing touches a server — tools you've used even work offline.
Compress JPEG XL images entirely in your browser — decoded and re-encoded by libjxl on your own device. Pick a quality or an exact target size; the result stays a .jxl. Nothing is ever uploaded.
How it works
- Drop files anywhere on the page, click to browse, or paste with ⌘V.
- Pick a quality or preset — or set an exact target size and let the tool find it.
- Compress, compare before/after, and download — individually or as a ZIP.
When a JXL can still shrink
JXL files saved at high quality, exported losslessly, or produced by cameras and tools with conservative defaults carry more bytes than their content needs. Re-encoding at a sensible quality routinely halves them. Files that were already tightly compressed have little left to give — when re-encoding would grow a file, the original is returned untouched, so a batch run never makes anything worse.
Quality, target size, or lossless
The quality slider is the everyday control; target-size mode finds the best quality under a byte cap. Because the output stays JXL, this is for trimming archives in place — for copies the rest of the world opens, JXL to JPG is one click away.
Frequently asked questions
How much smaller will my files get?
High-quality or lossless sources often drop 40–70%; already-tight files may not shrink at all — those come back unchanged rather than bloated.
Does the file stay a JXL?
Yes — same format, same extension, just fewer bytes. Players and tools that opened the original open the result.
Can I set an exact size?
Yes — switch to target-size mode and type a cap like 500 KB; the tool searches out the best quality that fits for every file in the batch.
Is it private?
Yes. The pixels are decoded and re-encoded right in your browser — images are never uploaded, and the server does nothing but deliver this page. Close the tab and no trace of your photos remains. Want proof? Run one file through, switch your connection off, and run another — it still works.